The hi-tech equipment has been introduced to allow officers to test vehicles at the roadside for the presence of the new fuel marker, which was introduced into supplies intended for use in agriculture and construction industries in April. The new marker is resistant to laundering techniques known to be used by criminal gangs and significantly improves HMRC's capability to detect fraud.

Previously, the test for the new marker was completed at a laboratory, leading to a delay in identifying illicit fuel and further action being taken. The new equipment will now be installed in 49 HMRC Road Fuel Testing Unit vehicles throughout the UK and used to analyse fuel samples taken at the roadside and at retail premises, starting in Northern Ireland.

Exchequer Secretary to the Treasury, Damian Hinds, said: “I am delighted to see first-hand the new roadside testing equipment in action. Together with the new marker it will play an important part in the fight against fuel fraud.

“At a time when the government’s priority is cutting the deficit, it is unacceptable that criminals are cheating the system. The new marker and testing equipment are part of the significant investment we have made in HMRC to tackle avoidance, evasion and fraud to make sure all businesses and individuals contribute to the tax revenue that is used to fund vital public services.”

Illicit diesel is estimated to make up 13 per cent of the market share of diesel in Northern Ireland and costs the taxpayer around £80 million each year in lost taxes.

The government will monitor the success of the marker during the first six months, to make sure it is delivering results in the fight against fuel fraud. HMRC will publish an evaluation in the autumn.